Battery technology on electricity network an Australian first

In an Australian first, Ergon Energy expects to be
installing new battery-based technology called Grid Utility Support Systems
(GUSS) to help power sections of its electricity network by mid-2015.

The news comes with the announcement of S&C Electric
Company winning an Ergon tender to provide 20 of the ground-breaking GUSS units.

GUSS works by charging batteries overnight when
electricity use is at its lowest and discharging them during the day if
required when energy use peaks.

Designed,
developed and proven by Ergon from an initial concept in 2006, the GUSS units are
an advanced, cost effective technology solution that will improve the quality
and reliability of electricity supply to rural customers on constrained single
wire high voltage distribution voltage lines, known as SWER (Single Wire Earth
Return).

"Traditional
augmentation solutions to constrained SWER lines where demand on that line is
exceeding its capabilities can cost in excess of $2 million" Ergon Chief
Executive Ian McLeod said.

"GUSS
units are not only a quicker solution than traditional network augmentation,
but the money we can save will ultimately put downward pressure on electricity
prices."

Additionally
customers on constrained networks who have had to limit their demand due to the
available capacity may be able to access additional supply.

"This is a first for Ergon and Australia," said Ergon Chief
Executive Ian McLeod.

"This technology has been proven and made ready for real-world
deployment without subsidies to Ergon which is also unique for this kind of
technology.

"Using a battery-based system in place of traditional network
augmentation will not only deliver better value for Ergon and customers, it
will help drive similar technology and integration on the electricity network,"
Mr McLeod explained.

Ergon finalised a successful trial of prototype GUSS units in Far
North Queensland last year and will now roll the systems out strategically to
sections of SWER network.

GUSS units could reduce SWER network augmentation costs by more
than 35 per cent on current estimates. The first production units are expected
to be built later this year.

They will provide 25kVA and 100 kilowatt hours nominal
capacity per unit, enough to power the average home for up to five days.

The units utilise a total of 50 Lithium-Ion type batteries
and were developed by a team of Ergon engineers. Trials of the system since
2011 have proven the concept on Ergon's SWER network.

In a further bonus for other new technologies, GUSS units
will also help Ergon's network interact with customer solar PV installations
more effectively and help avoid costly issues sometimes created by exported
power from rooftop solar.

Ergon predicts it could be deploying many hundreds of GUSS units
across its SWER network in coming years.

Ergon operates around 65,000 kilometres of SWER
network servicing more than 26,000 customers. SWER has proven to be a low cost
and reliable way of servicing low customer densities in rural and remote
communities throughout the state.

GUSS and
future capabilities – Ian McLeod explains:

"There is a commonly accepted theory that in the
future we could be combining home storage of power connected to, and backed up
by, the existing electricity network," Mr McLeod said.

"When we talk about power "stored" at home, this
could be through solar-charged batteries in your house, thermal storage such as
hot water storage units or even your electric car connected at home," he said.

"The process of sharing stored energy around
existing networks presents challenges however, but GUSS is delivering many
answers to this puzzle.

"Combining and sharing stored power across multiple
customer premises around sections of electricity network is a solution to peak
demand issues – a conundrum under examination in the electricity industry.

"If stored energy could be fed back into the
network to help relieve peak demand on our network, this could mean less investment
needed on infrastructure and hence less cost needed to be passed on to
customers.

"GUSS represents a big step forward in Australian utilities'
adoption of storage technologies."